Research On Multi-objective Optimal Configuration Of Cogeneration Microgrid

In recent years,various countries and regions have vigorously promoted renewable energy generation to ease energy shortage and reduce pollution emissions.The cogeneration microgrid can use wind energy,solar energy and cogeneration equipment to provide users with electric energy and heat energy,which improves the energy utilization rate and stability of energy supply.It can also solve the energy supply problem in remote areas.Therefore,the cogeneration microgrid has received a lot of attention.When the capacity of each distributed device in the microgrid system is not properly configured,it will have a great impact on the stability of the system and operation.Therefore,the reasonable capacity configuration of each device is an important guarantee for the cogeneration microgrid to meet the energy supply stability and certain economic requirements as well.In this paper,the capacity configuration of the cogeneration microgrid including wind turbines,photovoltaic panels,electric boilers,micro gas turbines,lithium ion batteries and heat storage tanks is studied.Firstly,the structure of the microgrid system with cogeneration of heat and power is analyzed and the configuration model framework is built.The working characteristics of each micro source were analyzed and the output model was established.Aiming at the uncertainty between the wind-solar power output,the electric load and heating load,the k-medoids clustering algorithm was adopted to extract typical scenes from the historical meteorological and load demand data to solve the problem.Secondly,a multi-objective configuration model considering the economy,reliability and energy exchange with the main grid of the microgrid is established.The first objective function is the lowest economic cost,including operation cost,acquisition cost and maintenance cost.The minimum dependence of the microgrid on the main grid is taken as the second objective function,which is expressed as the ratio of the electric power provided by the main grid to the total electric load demand.In this paper,operation strategies for different electricity sale modes and different selection combinations are formulated to determine the optimal configuration and selection combination of heating equipment and explore the configuration results of cogeneration microgrid under fixed price and time-of-use price electricity sale modes.Thirdly,the multi-objective cuckoo search algorithm is used to solve the objective function,and the non-dominated solution set obtained by the algorithm is processed by technique for order of preference by similarity to ideal solution,and the configuration capacity of the final device is obtained.Finally,the program of solving algorithm is written on Matlab platform to calculate the solution of the model.A case was selected to analyze the model.The results showed that the proposed method can get reasonable configuration and can effectively reduce the cost of the microgrid and the dependence on the main grid,which proves the effectiveness and reliability of the proposed method.The model provides a reference for the optimal configuration of the microgrid.